Preloaded triple roller entry guide

ABSTRACT

A triple roll entry guide where the guide has two sets of operation, a first which operates as a standard triple roller entry guide. Here the guide functions as a standard guide wherein three levers are pivoted about a work product axis to guide the work product into the reduction rolls of the mill. The guide will accept a predetermined size range of work products. In this instance the rollers of the guide overcome the force holding the levers in their usual working position and force the levers to assume a new position which the work product is accepted in the guide. This is the second method of operation, and in it the levers of the guide are “preloaded” so that the guide functions as a standard guide under prescribed conditions. 
     Under conditions which lead to the acceptance of a work product of a larger diameter in the predetermined size range the levers of the guide overcome the force which limits the maximum position of the levers of the guide and the work product is accepted by the guide.

The subject matter of this patent application is closely related to that of U.S. Pat. No. 5,937,689 which issued Aug. 17^(th), 1999.

The following description of this invention will describe an apparatus and method of rolling steel with a triple roller entry guide. It will be noted that the entry guide of this invention is used only when bar is being produced in the rolling process, not when the desired end product is in the form of sheet.

The entry guide of this invention is of the triple roller type, as opposed to the double roller entry guide which was used almost exclusively before the triple roller entry guide was introduced. The triple roller guide is a good deal more robust, wears significantly longer and thus does not lose accuracy due to wear, and because of its longevity in the workplace, it has almost won universal acceptance in the rolling field for rolling steel bar.

The triple jaw guide of the prior art is preset to some certain maximum previously predetermined dimension and all attempts to feed work material which is to be reduced into the guide, which has a diameter of which is slightly greater than this preset dimension at which the guide is set will be resisted by the guide. Although this is fine in theory, it can lead to stoppage in the rolling process when the guide refuses to feed material to the reducing rollers. Furthermore the guide has to be reset for each individual size in the range of bar diameters, resulting in mill down time.

In order to deal with a predetermined size range of bar diameters without resetting the guide it is proposed to make the jaws of the guide more flexible in adjustment so that during a standard run the jaws of the guide function as in prior art guides, that is the three jaws work in the range set for the guide, so that the guides the work product to the reducing rolls of the mill in a normal fashion.

As long as the diameters of the work product stay within a preset value, the rolling process continues and the work product is reduced by the reducing rolls. The jaws of the guide are permitted to open slightly wider than do the jaws of prior art guides, permitting the work product to pass through the guide and be reduced by the reducing rolls of the mill. This saves the time required to change the set-up of the guide and the guide so equipped can now be operated in the previous range (smaller diameter) without any delay in setting the guide to the smaller diameter work product. This saves time when a rolling process is involved. Time, like everything else, counts when a steel mill is down and the management is judged by the number of hours that are lost due to malfunctions of the mill.

It is to deal with such situations such as these that the present invention evolved. The triple guides of the prior art had little tolerance for the acceptance of work product whose diameter was slightly greater than a certain preset value of the guide.

The present invention utilizes a guide which has a funnel shaped opening, has three jaws carrying rollers which are set to guide material of a preset diameter. If, however, the material being fed to the guiding device is of a larger size, such that the diameter of the work product is slightly greater than said preset diameter, the guide will accept the slightly oversized work product and feed it to the reducing rollers anyway. This is made possible by the construction of applicant's device in which the jaws will resistibly open against a certain “preload” force to accommodate the larger diameter in the range of sizes of work product.

SUMMARY OF THE INVENTION

The guide of this invention follows the construction of the prior art invention except that a certain “pre load” has been built into the device. The guide of the present invention resistibly accepts material that would not be accepted by the prior art guide device, and the guiding process is allowed to continue even in the presence of larger diameter material in a pre-specified size range to the guide.

The guide of this invention has a funnel shaped admission device which leads the hot work product to a triple jawed guiding device. Here the opening of the jaws of the improved device are set and calibrated as in guides of the prior art, but the jaws may be resistibly “opened” past this position further to accept a work product of a larger size. This is accomplished by the use of a “Pre set spring loaded” member which “kicks in” and allows the jaws of the improved guide to move outwardly and temporarily accept the oversized work product.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective sectional drawing of a guide of the Prior Art;

FIG. 2 is a perspective sectional drawing of the guide of this Invention.

FIG. 3 is a representative drawing of part of the guide of this invention, showing an enlarged section where the “pre load” occurs.

FIG. 4 is a partial sectional view of part of the guide of this invention, showing how the adjustment of the opening of the jaws occurs.

FIGS. 5, 6, 7 and 8 show how the “pre load” is adjusted

DESCRIPTION OF THE PREFERRED EMBODIMENT

The principal of the standard triple jaw guide as shown in FIG. 1 is briefly described in the following passage. Reference may be had to applicant's prior patent referred to above for a complete explanation of the operation of the triple jaw guide. The triple jaw guide 10 as shown in FIG. 1 is shown having a work piece 12 passing there through from right to left. The work piece 12 must pass through a funnel shaped member 14 which is held in place by an intermediate member 16, which is part of stationary ring 18 on which jaws 20 are mounted.

Jaws 20 (of which two are shown) are mounted on pivots 22 which are permanently located in ring 18. Springs 24 assure that jaws 20 always present an opening which is a maximum for the passage of work product there through.

The adjustment of the opening of guide 10 is accomplished by the lateral movement of ring 26 which is mounted on the member 16 and moves to the left or right as determined by the direction of twist of the ring 26. A sloping face 28 on the ring 26 contacts each lock screw 30 of the jaws 20 to adjust the jaws 20 to a selected opening. The original work piece opening may require individual adjustment of the levers or jaws 20 in order to centre the work 12 in the guide 10. This is done by suitably adjusting the lock screws 30 against the sloping face 28 of ring 26. When the jaws 20 of the guide 10 are individually set so that the work piece is centred in guide 10 the guide may be opened or closed by twisting ring 26 until the desired setting of the opening for guide 10 is achieved. It must be remembered that once the jaws of the guide are set, the setting is rigid. This setting remains in the guide until the guide is altered.

Referring now to FIGS. 2 and 3, the applicant's improved guide 100 is shown in a partial sectional view. Here guide 100 is provided with three levers or jaws 110 (two of which are shown). Guide 100 is shown having a funnel shaped member 102 for guiding the hot work product 104 there through from right to left. Mounted on funnel shaped member 102 is a body 106 which surrounds the funnel shaped member 102 and is extended to form a ring 108. Pivoted levers or jaws 110 of the guide 100 are mounted for rotation about pivots 112 which are journalled in body 100. One end of the pivoting jaws has roller 114 mounted therein. Roller 114 is the equivalent of roller 18 of the prior art guide and serves to contact the hot work product and direct it to the reducing rolls (not shown).

A set of springs 116 are mounted in the guide 100 urge the jaws 110 apart to open the jaws 110 to the “maximum” opening permitted by the setting of the guide. Here a set of lock screws 118 are shown contacting ring 120 of guide 100. It is also in this position that the jaws 110 may be adjusted to centre the work product 104 passing through guide 100 by adjustment of lock screws 118.

Ring 120 is made to have a sloping surface 122 for the ends of lock screws 118 to slide upon. Ring 120 is mounted to slidingly fit on surface 124 where ring 120 contacts and surrounds member 102 of the guide 100. Member 106 serves to present a smooth cylindrical outer surface 124 for the lateral motion of ring 120 thereon.

The ring 120 is now set so as to guide the centred work product between rollers 114 and any movement (laterally) of ring 120 will open or close the opening presented by rollers 114 to the work product 104. Rollers 114 will lead the work product 104 directly to the reducing rolls of the mill (not shown).

FIG. 3 shows is a partial sectional view of the guide 100 with components of the “pre load” portion in enlarged format. Here it will be seen that a bolt 126 passes through clearance hole 132 of ring member 134 and threadedly engages ring 120 at threaded hole 128. A spring 130 surrounds bolt 126 and spring 130 which serves to “pre load” the jaws 110 of the guide 100. Ring 134 (which is threaded on to member 106) controls the lateral position of ring 120. It is seen that ring 134 is movable laterally by turning ring 134 on boss 106, of course ring 120 must turn with it. This adjusts the opening of the jaws 110 but does not altar the “pre load” built into the guide 100. FIG. 4 shows the position of the various parts of the guide 100 for a setting of the jaws 110 which permits jaws 110 to accept a work product which is of substantially larger diameter than previously. Note that the “pre load” does not change when the jaws 110 are individually adjusted as previously described.

FIG. 4 shows how to increase the “opening” of jaws 110. Ring 134 is twisted on the threads 138 of member 106 to move ring 120 to the right. As previously, the twisting of ring 134 merely moves ring 120 to the right to provide the necessary adjustment of the opening provided by rollers 114, without changing the “preload” of the device 100.

The method of adding or reducing the “pre loads” to ring 120 is shown in FIGS. 6, 7, and 8. The balance of the construction of the device remains the same except for the addition of the “pre loads”. Ring 134 is threaded on to boss 106 at threads 138, as previously and ring 134 continues to urge the sloped surface 122 against the ends of jaws 110 via lock screws 118. Using the method shown here it is possible to add the preloads in a predictable manner.

For instance, it is possible to double the “pre load” supplied by the guide 100 as in FIG. 5 in a known fashion. Suppose that the “pre load” existing at guide 100 is set to some value “x” by the setting presently set in guide 100 (see FIG. 5). To increase the “pre load” to a value of 2× the number of “presets” now is doubled on the device 100. This is shown by the number of “presets” 128 and 130 embodied in FIG. 6.

This invention solves the problem of using expensive “down time” for an operating steel mill to adjust guide openings which must be adjusted to accommodate a work product where the diameter temporarily exceeds the opening in the guide. Previously this situation would have entailed shutting down the operation of the mill and adjusting the guide opening. This requires time. It is by the use of this invention that this situation is avoided.

Many modifications and other embodiments of the invention will come to mind of one skilled in the art, having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed, and that the modifications and embodiments are intended to be included within the scope of the dependent claims. 

1. A roller entry guide for guiding a work product a longitudinal axis comprising: a hollow housing having multiple pivots incorporated therein, said pivots being located in a plane lying orthogonal to said longitudinal axis, pivotably mounting at least three roller assemblies at equally spaced angles about said longitudinal axis, said roller assemblies comprising a lever having a first end and a second end and a pivot point located between said ends, said first ends of said lever assemblies having a shaped wheel mounted for rotation thereon, for engaging said work product so that an opening for said work product is formed by said wheels, said second ends of said lever assemblies bearing against a common member mounted on said housing and so that the second ends exert a first force on said common member when a work product of a first diameter passes through said opening, the second ends of said lever assemblies exerting a second force on said common member when a second work product of a larger diameter passes through said opening, said second force being greater said first force, said common member moving against a second resilient member to establish a reaction force when said second force exceeds a predetermined value.
 2. A roller entry guide as claimed in claim 1 wherein the first and second forces are applied evenly to said common member by said lever assemblies.
 3. A roller entry guide having a body on which a plurality of identical levers are pivotably mounted thereon so as to pivot in planes which are equally angularly spaced about an axis where a steel strand is being rolled, said levers each having a roller mounted for rotation at the first end of said lever, said rollers contacting said steel strand, and guiding it into work reducing rolls of a steel mill, said rollers being adjustable to roll steel strands of various sizes, said levers transferring the force created by said rollers contacting said strand to the remote end of each lever, the second end of each lever contacting a common member, said common member being positioned so that any force exerted on said common member by the second ends tends to move said common member laterally, said common member resisting the force exerted by said second ends of said levers until said force exceeds a predetermined value, at which time said common member moves laterally and permits said levers to move.
 4. A roller entry guide having at least three rollers for guiding a work product to the reducing rolls of a reducing mill, said rollers being mounted at the ends of at least three levers so as to form a first opening formed by said wheels for the passage of a work product of a first diameter there between along an axis through said entry guide, said opening in said guide being adjustable to resistably open beyond the limit set by said first opening so as to accept a pre-determined range of work product of slightly greater diameter than said first diameter, said levers being pivoted on a set of pivots which are equally spaced about said axis and lie in the same plane on said entry guide, orthogonal to said axis, said pivots on said levers lying between the ends of said levers, such that the ends of said levers remote from said rollers rest upon a common conically shaped surface of a spring loaded circular member, said ends of said levers pushing said common member sidewise against said spring loaded circular member when a work product of slightly greater diameter than said first diameter passes through said opening formed by said wheels, said levers being forced to return by said common member to form said first opening when said work product diameter decreases to its first diameter.
 5. A roller entry guide as claimed in claim 4 wherein the levers are substantially the same.
 6. A roller entry guide as claimed in claim 5 wherein the wheels all have the same shape.
 7. A roller entry guide as claimed as claimed in claim 6 wherein said common member slides on a circular cylindrical surface formed on said guide to adjust said opening.
 8. A roller entry guide as claimed in claim 7 where the position of said spring loaded member is adjustable laterally by a screw threaded ring. 